BACKGROUND:Head and neck cancer is the sixth most common cancer reported worldwide. In many cases, the level of aggressiveness of therapy adopted in cancer patients may cause the alteration in oral microbiota; the emergence of potential pathogens may cause opportunistic infections in already immune-compromised individuals leading to increases in morbidity and mortality. Hence, this study was conducted to assess the oral microbial profile in oral cancer patients before and after radiotherapy. MATERIALS AND METHODS:A total of 145 oral swabs were collected before radiotherapy ( = 96), 3 months postradiotherapy ( = 25), 6 months postradiotherapy ( = 12) and controls ( = 12). The samples were inoculated into brain-heart infusion broth and later in different media for bacterial isolation. The isolates were subjected to phenotypic characterization by automatic identification system. RESULTS:Among the 96 samples studied from the preradiotherapy patient samples, species ( = 28) were the predominant isolate, followed by species ( = 16), species ( = 6) and Enterococcus species ( = 6). Of the 25 samples studied 3 months after radiotherapy, ( = 4) was isolated and 12 samples studied after 6 months of radiotherapy species ( = 4) and species ( = 3) were isolated. Among the control group ( = 12) screened, ( = 3) is the predominant bacteria isolated. CONCLUSION:High prevalence of sp. was found in patients of oral cancer before radiotherapy, while and species and species are the significant pathogens isolated in postradiotherapy cancer patients.

OBJECTIVES:The purpose of this prospective clinical study was to identify the bacterial spectra on the surface of oral squamous cell carcinomas (OSCC) in comparison to oral mucosa of patients with a higher risk to emerge an OSCC and a control group to determine their susceptibility to various common antibiotics. MATERIAL AND METHODS:Swabs from 90 patients, 30 patients of each group, were cultured on media for aerobes and anaerobes and tested with agar diffusion and Etest. RESULTS:The predominant pathogens of the normal healthy oral mucosa were aerobes. The ratio between aerobes and anaerobes was 2:1, balanced in risk patients and inverted in the OSCC group. Altogether, 1,006 isolates were cultured. The most frequent strains were 47 viridans streptococci, 30 Staphylococcus species, 14 Enterococcus faecalis, 36 Neisseria species, 14 Escherichia coli, and 23 other aerobes, 66 Peptostreptococcus species, 39 Fusobacterium species, and 34 Prevotella species. The resistance rates in the OSCC group were penicillin 40%, ampicillin 57%, doxycycline 23%, clindamycin 47%, and amoxicillin/clavulanic acid 20%, but up to 100% of pathogens were susceptible to azithromycin, telithromycin, levofloxacin, and moxifloxacin. CONCLUSION:Gram-negative anaerobes play a decisive role in the development of postoperative infections in patients with OSCC. This tumor special type of colonization does not agree with the normal flora of the oral cavity. CLINICAL RELEVANCE:Biofilms on OSCC surfaces provide an important reservoir for anaerobic bacteria. As a consequence, a proposal for an antibiotic prophylactic regime should be given.